Is Warren Buffett Signaling Lower Rates Of Return For Stocks?ForbesWhile it isn't unusual to see Warren Buffet's kitty grow a substantial amount in a year's timeframe such as $6.9 billion in 2010 and $8.8 billion in 2012 (see a Google Doc I created with Berkshire Hathaway's cash balances going back to 2000) the $6.8 …